need help in ERD scenario

We have been asked to analyze the data requirements and develop a conference management system to keep information about all the conferences and papers presented in the conferences.

Conferences are conducted in different parts of the world. Each conference is identified by its name and year of the conference. The conference has a starting and ending dates, fields, and conference location (country, venue where that conference is held, and country international telephone code). The conference may also organize some social activities. For each activity, the system stores the name of the place to be visited, date, duration and the price of visiting that specific place.

A conference would receive lots of paper to be submitted to the conference, but only selected number of these papers will be accepted. Each paper is identified by its main author and title. The paper also has number of pages and secondary authors (if any). In addition, each paper is given a type (e.g. S: Survey, B: Brief, F: Full, P: Poster). A paper can be submitted in only one conference and many papers may be submitted to the same conference. Once a paper is submitted in a conference, the system sends a message to the author acknowledging the paper submission. For each submitted paper, the system stores whether this paper is accepted or not.

If a paper is accepted, at least one author should attend the conference to present the paper. We want to keep information about the author who presented the paper in the conference. Each author is identified by a unique AID, has a name, address, affiliation and contact telephone number of this affiliation. An author can write one or more research papers and a paper have one main author and one or more secondary authors. Furthermore, an author may attend many conferences, for each attendance we need to store the attendance type (presenting a paper, visitor, student,..) and if the attendee has any disability needs.
The system should also store the number of papers submitted and accepted for each conference, in addition to number of attendees. Authors attending the conference may register for one more of the activities offered by the conference. For each registration, the system store number of persons accompanying the author.

Task to be done:

You are required to do the following tasks:

1. Use the above information to build an E-R diagram. Note that there is some missing information in the scenario. To complete the task, you can make reasonable assumptions about the missing information. All the assumption made by you must clearly be mentioned in the report before making the ER diagram.

2. Map the ERD to relations. Identify the primary key for each entity.

3. For each of the relations created, indicate its normal form. If the relation is not in the 3NF, decompose it into 3NF relations.